The objectives of this record-linkage investigation are: 1) to evaluate the risk of second cancers following treatment for cancer of the uterine corpus (radiotherapy, surgery, and/or hormones) by type of uterine corpus cancer (uterine sarcoma, non-uterine sarcoma), time since treatment and age at treatment; and 2) to select those organ sites for which additional detailed information on radiotherapy and other risk factors might be valuably pursued in a future detailed case-control or case-cohort investigation.